This invention concerns a multipurpose device for rolls of round bars for reinforced concrete.
To be more exact, the invention concerns a multipurpose device for rolls of round bars used for reinforced concrete, the device being located upstream of machines which process the round bars, such as straightening machines, shears for shearing to size, shaping machines, forming machines, etc.
These machines which process the round bars may carry out one or more of the operations of straightening, measuring, shearing and/or bending according to requirements.
This description speaks of sections as round bars, preferably round bars produced with a hot or cold process for use in reinforced concrete, but the invention is also applied properly to sections having different cross sections such as square, hexagonal, polygonal, etc. cross sections and used also for other purposes.
Document IT 83347 A/90 (EP-A-91102615.1) describes a rotary turret winder for rolls of round bars for reinforced concrete, the winder being located upstream of a user machine such as a straightening machine, shears and/or bending/shaping machine.
The above rotary winder comprises at least two roll-holder reels, and when the round bar being processed has to be replaced, for a change of size for instance, the rotary winder has to be rotated to bring the new roll-holder reel to the working position.
The rotary winder of the state of the art is associated with one single machine of the above described type or with one single assembly of machines positioned in series.
The work of replacing the round bar by means of the rotary winder of the state of the art entails a long non-productive time spent in changing the roll or changing the size since on each occasion it is necessary to withdraw/thread the round bar from/into the straightening assembly located outside the rotary winder.
Moreover, the above rotary winder of the state of the art cooperates downstream with a straightening assembly which has of necessity to be complex so as to be able to perform the straightening of coils which have a curvature, due to being wound up, on the plane on which they lie and also have a deformation by twisting due to their being unwound and drawn.
GB-A-1,075,789 of 1964 discloses a turntable device located in a rolling line producing coils. This device has the purpose of winding and unwinding coils in concentric spirals and may cause the coils to pass through a straightening assembly during winding and unwinding. This teaching dating back to 1964 has never met with acceptance in devices which unwind round bars for building work either because it belongs to an old technology or because people have never understood that pre-straightening or straightening of round bars for building work can be carried on during unwinding from a roll of coils in bulk, this too although there has been felt for a long time a need to supply to the working machines immediately downstream a round bar already straightened when it comes off a roll. Moreover, the uniform and expected winding and unwinding of the spirals of the coils cause no difficulty for the straightening assembly.
FR-A-2.182.594 of 1972 discloses a rotary winder bearing two or more rolls of wire, which is wound in coils substantially in bulk. This teaching was disclosed a good eight years later than GB-A-1,075,789 and a good twenty years earlier than the present application. The prestraightening system is the classic one which has been retained up to the present time with central extraction from above, which is not suitable to feed usage machines such as straightening machines, shears and/or bending/shaping machines. The content of FR-A-2.182.594 is unsuitable for installation of straightening assemblies, precisely because of the axial outlet system which is connected to the deviation wheel.
It should also be borne in mind that the devices disclosed in the state of the art documents can work, during unrolling, with one single downstream machine, a four-high rolling mill stand or a drawbench respectively. Furthermore, none of the teaching of the prior art teaches the overcoming of the typical problems of introduction into the machines downstream.
Furthermore, none of the devices of the state of the art provides the ability to process a wide range of different sizes or to supply different machines or machines performing different functions at one and the same time.